Firing mechanism of ordnance



A. T. DAWSON AND G. T. BUCKHAM.

FIRING MECHANISM OF ORDNANCE.

APPUCATION FILED Nov. 13. l9l7.

1 ,360,73 1 Patented Nov. 30, 1920.

2 smzns sussr 1.

MMMM W A. T. DAWSON AND G. T. BUCKHAM.

FIRING MECHANISM OF ORDNANCE.

APPLICATION FILED NOV-13. 1917.

1 360,73 Patented Nov. 30, 1920.

2 SHEETS-SHEET 2.

Shit"? ARTHUR TREVOR DAWSON AND GEORGE THOMAS DUCKHAM. OF WESTMINSTER,

LONDON, ENGLAND, ASSIGNORS TO V'ICKERS LIMITED, OF WESTMINSTER, LON- DON.

FIRING MECHANISM OF ORDNANCE.

Specification of Letters Patent. Pgjtgnted N 30 1920.

vApplication filed November 13, 1-917. Serial No. 201,846.

T 0 all whom it may concern:

Be it known that we, Sir A THUR TREVOR DAWSON, knight, and Sir GEORGE THOMAS BUCKHAM, knight, both subjects of the King of Great Britain, residing at Vickers House, Broadway, Westminster, in the county of London, England, have invented certain new and useful Improvements in or Relating to the Firing Mechanism of Ordnance,

of which the following is a specification.

This invention relates to the firing mechanism of guns of the so-called non-recoil type in which the barrel open at each end and receives in addition to the projectile and the powder charge a compensating mass which when the gun is fired is ejected from the rear end of the barrel, the-inertia of this mass being substantially equal to that of the projectile so that the recoil force due to the firing of the projectile is more or less neutralized. In such guns it has been proposed to construct the barrel in two portions, viz. a forward portion (herein termed the fixed portion) and a .rear portion (herein termed the movable portion) connected together by interrupted threads or collars, the movable portion after it has been unlocked from the fixed portion being capable of displacement to enable the gun to be loaded.

According to the present invention the firing mechanism in a gun of the abovetype comprises a spring controlled striker or firing pin and means, operated by the device for unlocking the movable barrel portion, for retracting the striker before any unlocking movement of the said barrel portion occurs; the said means also serve to cock the striker during. the movement of the barrel-portion toward its open or loading position. The above described arrangement provides adequate safety against premature firing and insures an easy operation during the compression of the striker. spring while leaving sufficient reserve force for effecting the extraction of the cartridge case. The striker is released to fire the gun by a trigger which is mounted on the hand grip portion of a training arm onthe fixed barrel portion and operates upon the sear through a system of rods and levers.

In order that the said invention may be clearly understood and readily carried into effect, we will describe the same more fully with reference to the accompanying drawings, in which Figure 1 is a side elevation showing part ofa gun of the kind referred to provided wlth a constructional form of our improvements.

Fig. 2 is a section taken approximately on the line 2, 2 of Fig. 1 viewed from the left.

Fig. 8 is a plan of Fig. 2 with the right hand portion thereof in section on the line 3', 3 of Fig. 2 and Fig. 4 is a local section on the line 4, 4 of Fig. 1.

A is the fixed barrel portion and B is the movable barrel portion connected together by interrupted threads or collars. In the example shown the means for displacing the movable barrel portion B are similar to the means set forth. in the specification of our United States patent application No. 201,845 and comprise a sleeve C rotatably mounted upon a spindle B and actuated through bevel gearing by a hand lever B".

This sleeve carries a horizontally arranged roller pin C (Fig. 1) engaging with a recess 6 (see F 1g. 4) in a cam band B attached to the-movable barrel portion B, this versely to the axis of the gun within a casg ing D connected to a band D secured to the fixed barrel portion and which passes through a hole in the wall of this barrel portion. D is the striker spring which is situated within the casing D. The means for retracting and cooking the striker comprise a cam groove E formed in the sleeve C, with which groove engages a ball pin E on the rear end of a longitudinally sliding rod E The other end of this rod is con nected to one arm of a bell crank lever E pivoted to a bracket A This bracket has a lug A connected to an elevating are A attached to the fixed barrel portion A. The other arm of this bell crank lever has ahole through which passes a rod 6 terminating at its lower end in an inverted T the arms tions d, cl on a member D attached to the,

striker. The cocking lever 6 has a handle 6" for enabling the striker to be recocked. Loosely surrounding the rod and arranged in contact with the upper surface of the last mentioned arm of the bell crank lever, is. a washere between which and an enlarged. portion at the lower end of the rod. 6." a spring a is disposed. The re-cocking movement of the lever 0 takes place independently ofthe. bell crank lever E owing to the loose connection between the rod 6 and the; bell crank lever. The said re-cocking movement compresses the spring 6 and this springreturns the cocking lever, when released, to its normal position so asnot to interfere with the throw of the striker.

When the movable barrel portion is fully striker is retracted bv' the said steep ortion of the cam groove before the rol er pin, C comes into contact, with, the left hand wall of'the recess b that is to say before any unlocking-movement is imparted to the movable barreli portion. v Continued. movement of the sleeve C in the same direction then unlocksthe movable barrel portion from the fined: barrel )ortion during which time the cam groove effects the cooking of the striker D'- as followsz Th'ecam grooy ecauses the rod E to moverearward, thereby lifting the striker through themediumof the bell crank lever E the rods 6, e"; the-lever-e the armse, 6*; the pinsd d and the member D", until the striker reaches a position in which the nose of a sear f hereinafter referred to can engage withthe underside of the member-B the said sear. being displaced-to its engaging position by; a bent; spring f F is the aforesaid training arm. (so termed. because the gunner, by pushing or p ulling on it, trains the gun) which is carried by a socketF" in, the trunnion arm on the band D 'secured to the fiXedbarrel portion A and f is the trigger pivoted on the hand. grip portion of the said training arm. This trigger engages with a sliding pin or rod f which is arranged axially within the arm F. Theinner end of this sliding pin operates 11 on abellerank lever f 'connected'to an upright rod f whose lower part passes-through atransverse hole in the socket F and whose upper end is connected to a lateral arm f on th'e sear f. The aforesaid striker casing D carriesa detachable. cover d for the sear, this cover being dovetailed into the casing and being retained in place by the sear spring-orby a split pin.

t.- welclaim and desire to secure by Letters. Batentofthe United States is 1.,I n firing: mechanism for non-recoil ord- Rance having'a fixedebarrel-rportion and a mQVable barrelportion, the combination with. a device for unlocking the movable barrel-portion, of a spring controlled striker and means operated by said device, for retracting the striker before. any unlocking movement. of, said movable barrel-portion occurs.

2.. Infiring mechanism for non-recoil ord nance having a fixed barrel-portion and a movable barrel-portion, the combination witha device for unlocking: the movable barrel-portion, of} a spring controlled striker and means,. operated by said device; for retracti'ng the; striker before any unlocking movement. of said movable:barrel-portion occurs. and for. cocking the striker duri the movement ofthe movable barrel portion' toward the, open; oriloading position.

3;, Infirin'g; mechanism fornon-recoil ordnance having afixed barrel-portion andv a movable barreleporti'on the. combination of they striker. anda rotary member' havinga cam groove forv retracting, the strikenand a device operated by said rotary memberfor unlocking, the movable barrel-portion, said groove. retracting the. striker before. any unlocking movement of the movable barrelportionijoccursn 4'. Infiring mechanism. for non-recoil ordnance having, anfixed. barrel-portionand amovable barmllportion, the. combination of the. striker andarotary sleeve having a cam groove forretracting thestriker, and a device operated by said rotarysleeve for unlocking the. movable, barrel-portion, said TREVOR DAWSON, GEORGE "THOMAS, BU CKH'AML 

